The expression of metallothioneins (MTs) is finely regulated and they function in the homeostasis of essential metals (Zn and Cu), the detoxification of heavy metals (Cd and Hg), and the scavenging of hydroxyl radicals. The specific aims of this proposal are to determine the mechanisms by which i) cell-type specific expression of the MT genes is regulated in the deciduum, and 2) mouse MT gene expression Is Induced by oxidative stress and bacterial endotoxin. The aims will be approached by; a) identifying potential cis-acting sequence elements involved in elevated gene expression, using in vivo genomic footprinting, b) demonstrating specific DNA-protein interactions using in vitro DNase I footprinting, band shift and competition assays, and c) determining essential nucleotides required for the binding using mutational analysis, accompanied by in vitro footprinting, band shift assay and transfection assay. d) mapping MT gene flanking regions for DNase 1 hypersensitive sites associated with deciduum-specific ene expression. Delineation of the cis-acting elements involved in the cell-specific or oxidative tress/endotoxin-inducible expression of MT gene will eventually contribute to the identification and purification of the trans-activating proteins.